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1.
J Agric Food Chem ; 68(6): 1678-1683, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31957422

RESUMO

During submerged cultivation, the edible basidiomycete Fomitopsis betulina (previously Piptoporus betulinus) developed a fruity odor, strongly reminding of pineapple. Olfactometric analysis showed that this impression was mainly caused by the two (5E/Z,7E,9)-decatrien-2-ones. At the time of maximum concentration on the 5th day, the (5E/5Z)-ratio was 94:6. Three hypotheses were experimentally examined to shed light onto the genesis of the uncommon volatiles: first, an indirect effect of agro-industrial side-streams, such as cabbage cuttings, supporting good growth; second, an unsaturated odd-numbered fatty acid precursor; and third, a polyketide-like pathway. In the presence of 1-13C- or 2-13C-acetate up to five acetates were incorporated into the molecular ions of the C10-body. Addition of 1-13C-pyruvate or 1-13C-lactate did not confirm an odd-numbered starter of the polyketide chain. None of the methylketones was found in pineapple or any other food before.


Assuntos
Coriolaceae/química , Odorantes/análise , Compostos Orgânicos Voláteis/química , Acetatos/análise , Isótopos de Carbono/análise , Coriolaceae/crescimento & desenvolvimento , Coriolaceae/metabolismo , Cetonas/química , Compostos Orgânicos Voláteis/metabolismo
2.
Prep Biochem Biotechnol ; 50(1): 74-81, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31517565

RESUMO

Ectoine has fostered the development of products for skin care and cosmetics. In this study, we employed the marine bacterial strain Marinococcus sp. MAR2 to increase ectoine production by optimizing medium constituents using Response Surface Methodology (RSM) and a fed-batch strategy. The results from the steepest ascent and central composite design indicated that 54 g/L of yeast extract, 14.0 g/L of ammonium acetate, 74.4 g/L of sodium glutamate, and 6.2 g/L of sodium citrate constituted the optimal medium with maximum ectoine production (3.5 g/L). In addition, we performed fed-batch culture in the bioreactor, combining pH and dissolved oxygen to produce ectoine by Marinococcus sp. MAR2. The ectoine production, content, and productivity of 5.6 g/L, 10%, and 3.9 g/L/day were further reached by a fed-batch culture. Thus, the ectoine production by Marinococcus sp. MAR2 using RSM and fed-batch strategy shows its potential for industrial production.


Assuntos
Diamino Aminoácidos/metabolismo , Bacillaceae/metabolismo , Técnicas de Cultura Celular por Lotes/métodos , Microbiologia Industrial/métodos , Acetatos/análise , Acetatos/metabolismo , Bacillaceae/crescimento & desenvolvimento , Técnicas de Cultura Celular por Lotes/instrumentação , Reatores Biológicos , Meios de Cultura/química , Meios de Cultura/metabolismo , Desenho de Equipamento , Fermentação , Microbiologia Industrial/instrumentação , Citrato de Sódio/análise , Citrato de Sódio/metabolismo , Glutamato de Sódio/análise , Glutamato de Sódio/metabolismo
3.
Biomed Chromatogr ; 34(1): e4694, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31465553

RESUMO

A simple and rapid analytical method for the detection of trifloxystrobin, trifloxystrobin acid and tebuconazole in soil, brown rice, paddy plants and rice hulls was established and validated by liquid chromatography with tandem mass spectrometry. Acceptable linearity (R2 > 0.99), accuracy (average recoveries of 74.3-108.5%) and precision (intra- and inter-day relative standard deviations of 0.9-8.8%) were obtained using the developed determination approach. In the field trial, the half-lives of trifloxystrobin and tebuconazole in paddy plants were 5.7-8.3 days in three locations throughout China, and the terminal residue concentrations of trifloxystrobin and tebuconazole were <100 and 500 µg/kg (maximum residue limits set by China), respectively, at harvest, which indicated that, based on the recommended application procedure, trifloxystrobin and tebuconazole are safe for use on rice. The risk assessment results demonstrated that, owing to risk quotient values of both fungicides being <100%, the potential risk of trifloxystrobin and tebuconazole on rice was acceptable for Chinese consumers. These data could provide supporting information for the proper use and safety evaluation of trifloxystrobin and tebuconazole in rice.


Assuntos
Acetatos/análise , Fungicidas Industriais/análise , Iminas/análise , Oryza/química , Resíduos de Praguicidas/análise , Estrobilurinas/análise , Triazóis/análise , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Limite de Detecção , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Medição de Risco , Solo/química , Adulto Jovem
4.
J Sci Food Agric ; 100(2): 517-526, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31512252

RESUMO

BACKGROUND: Aroma is one of the most important aspects of fruit quality and can reflect the characteristics of different fruits. Aroma-active compounds can usefully be employed to trace the production areas of two citrus cultivars ('Eureka' lemon and 'Huapi' kumquat) and to evaluate their aroma quality. RESULTS: 'Huapi' kumquat peel displayed higher monoterpene and sesquiterpene compound content, whereas 'Eureka' lemon peel exhibited higher monoterpene and monoterpene aldehyde compound content. 'Eureka' lemon peel ('Wanzhou' cultivar) had higher nerol acetate and geraniol acetate compound content. Kumquat peel ('Suichuan' and 'Rongan' cultivars) had higher sesquiterpene content. In addition, 30 and 31 aroma-active compounds were observed in kumquat and lemon, respectively, based on their odor activity values. Principal component analysis (PCA) and hierarchical clustering analysis (HCA) results indicated that classification for production areas based on aroma-active compounds was useful. The selected aroma-active compounds have been checked as aroma quality parameters that could be used with multivariate analysis to establish a model of aroma quality evaluation. Higher aroma quality values from kumquat and lemon were collected from Rongan and Wanzhou cultivars, respectively. CONCLUSION: Aroma-active compounds can be used to discriminate production areas using multivariate statistics. An objective method was established to evaluate the aroma quality of citrus fruits. 'Huapi' kumquat and 'Eureka' lemon, which had the highest aroma quality, was harvested from the Rongan and Wanzhou production areas. This was the first time that the aroma quality of citrus fruits was evaluated using multivariate analysis. © 2019 Society of Chemical Industry.


Assuntos
Citrus/química , Odorantes/análise , Compostos Orgânicos Voláteis/química , Acetatos/análise , Aldeídos/análise , Frutas/química , Monoterpenos/análise , Controle de Qualidade , Sesquiterpenos/análise
5.
Food Chem ; 306: 125623, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31606633

RESUMO

In this study, apple juice was fermented using Hanseniaspora osmophila X25-5 in pure culture as well as mixed culture with Torulaspora quercuum X24-4, which was inoculated simultaneously or sequentially. H. osmophila inhibited the growth of T. quercuum, while T. quercuum had little effect on the growth of H. osmophila. The simultaneous fermentation consumed relatively more sugar and resulted in the highest ethanol content. The production of organic acids varied depending on the yeast species employed and inoculation modality. Esters and alcohols were the main volatile families produced during fermentation, while ethyl esters and terpenes contributed most to the temperate fruity aroma. Gas chromatography-olfactometry (GC-O) showed that 3-methyl-1-butanol, ethyl 2-methylbutanoate, phenylethyl alcohol, ß-phenethyl acetate, and ß-damascenone were the most potent odorants in all samples. This study suggested that simultaneous fermentation with H. osmophila and T. quercuum might represent a novel strategy for the future production of cider.


Assuntos
Acetatos/análise , Fermentação , Hanseniaspora/metabolismo , Malus/metabolismo , Odorantes/análise , Torulaspora/metabolismo , Bebidas Alcoólicas , Cromatografia Gasosa , Ésteres/análise , Frutas/química , Norisoprenoides/análise , Olfatometria , Vinho/análise
6.
Int J Med Mushrooms ; 21(6): 561-570, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31679228

RESUMO

The in vitro antioxidant effects of petroleum ether, ethyl acetate, and ethanol extracts isolated from Hericium coralloides were investigated. Overall, the ethyl acetate extract of H. coralloides (HcEAE) showed better antioxidant activity in vitro than the petroleum ether and ethanol extracts (HcPEE and HcETE, respectively) of H. coralloides. A comprehensive investigation of the antioxidant activity of the HcEAE in vitro indicated that it possessed superior antioxidant activity, with half maximal inhibitory concentration (IC50) values of 0.93, 1.84, 1.59, and 0.6 mg/mL against DPPH, hydroxyl, ABTS+, and superoxide (O2- ) radicals, respectively. To assess in vivo antioxidant activity, three different doses of HcEAE were orally administered in a D-galactose-induced aged mouse model. Administration of HcEAE significantly increased the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) and lowered the levels of malondialdehyde (MDA) in brains and sera of mice in a dose-dependent manner. A histopathology assessment indicated that the HcEAE could ameliorate the anile condition of the model mice. These results suggest that the HcEAE has potent antioxidant activity and could minimize the occurrence of age-associated disorders associated with free radicals.


Assuntos
Agaricales/química , Envelhecimento , Antioxidantes/análise , Extratos Celulares/farmacologia , Acetatos/análise , Envelhecimento/efeitos dos fármacos , Alcanos/análise , Animais , Catalase/análise , Extratos Celulares/química , Etanol , Radicais Livres/análise , Concentração Inibidora 50 , Masculino , Camundongos , Superóxido Dismutase/análise
7.
Environ Monit Assess ; 191(10): 628, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31502086

RESUMO

The present study was done to assess the dissipation behavior, decontamination, and half-life time of ready-mix formulation of trifloxystrobin (25% w/w) and tebuconazole (50% w/w) in okra and soil under the crop after foliar spray at fruiting stage. Samples of okra and soil were collected periodically, i.e., zero (2 h after spray), 1, 3, 5, 7, 10, 15, 20, and 25 days after third application at a 7-day interval. Residues of these fungicides were determined by gas liquid chromatography (GLC) equipped with electron capture detector (ECD) and gas chromatography-tandem mass spectrometry (GCMS-triple quadruple). The limits of quantification (LOQ) and detection (LOD) for both the fungicides were 0.01 and 0.003 mg kg-1, respectively. Washing alone with faucet water was found successful in minimizing the residues. Soil was free from residual contamination at fifth day after spraying in case of both the fungicides and at both the doses.


Assuntos
Abelmoschus/metabolismo , Acetatos/metabolismo , Fungicidas Industriais/metabolismo , Iminas/metabolismo , Resíduos de Praguicidas/análise , Solo/química , Estrobilurinas/metabolismo , Triazóis/metabolismo , Abelmoschus/química , Acetatos/análise , Descontaminação , Monitoramento Ambiental , Frutas/química , Frutas/metabolismo , Fungicidas Industriais/análise , Meia-Vida , Iminas/análise , Estrobilurinas/análise , Triazóis/análise
8.
Regul Toxicol Pharmacol ; 108: 104471, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31493441

RESUMO

Multi-locational supervised field trials were conducted in different agro-climatic regions in India to study dissipation of trifloxystrobin and tebuconazole in tomato after spraying a combination formulation (trifloxystrobin 25% + tebuconazole 50%, 75WG) at recommended doses: (i) single (trifloxystrobin 87.5 g a.i. ha-1 + tebuconazole 175 g a.i. ha-1) and (ii) double (trifloxystrobin 175 g a.i. ha-1 + tebuconazole 350 g a.i. ha-1). Fruit samples were extracted with ethyl acetate using a modified QuEChERS method. The residues (parent fungicides + metabolite) were analyzed and confirmed by GC-ECD and GC-MS, respectively. The half-life (t1/2) of trifloxystrobin and tebuconazole in tomato varied from 1.08 to 1.72 and 1.13 -to 1.64 days at single; and 1.27 to 2.13 and 1.24 to 1.96 days at double dose, respectively. Since maximum residue limit (MRL) at pre-harvest interval (PHI) of 5 days is impractical, as tomato is usually harvested and consumed almost everyday after the last spray, the risk assessment was performed at minimum PHI of 1 day. Accordingly, on the basis of supervised field trial data and using OECD MRL calculator, MRL of 0.5 and 1.5 mg kg-1 at single dose were proposed for trifloxystrobin and tebuconazole in/on tomato, respectively.


Assuntos
Acetatos/análise , Frutas/química , Fungicidas Industriais/análise , Iminas/análise , Lycopersicon esculentum , Resíduos de Praguicidas/análise , Estrobilurinas/análise , Triazóis/análise , Adulto , Criança , Exposição Dietética , Cromatografia Gasosa-Espectrometria de Massas , Meia-Vida , Humanos , Nível de Efeito Adverso não Observado , Medição de Risco
9.
J Chromatogr A ; 1605: 360350, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31378527

RESUMO

According to the recent proposal released by the European Commission for the revision of the 98/83/EC Directive, water suppliers will be requested to monitor the nine bromine- and chlorine congeners of haloacetic acids, HAAs, as well as the oxyhalides chlorite and chlorate, as disinfection by-products (DBPs) originated during the potabilization process. In this work, we propose a direct-injection method based on ion chromatography and mass spectrometric detection for the determination of the mentioned DBPs as well as bromate (already included in the 98/83/EC), implemented also for the following emerging HAAs monoiodo-, chloroiodo- and diiodo-acetic acids. The method was optimized to include the fifteen compounds in the same analytical run, tuning the chromatographic (column and gradient) and detection conditions (suppression current, transitions, RF lens settings and collision energies). To avoid matrix effect and to manage the instrumental conditions, optimization was performed directly in drinking water matrix. The method quantitation limits satisfy the new limits imposed by the future directive and range from 0.08 µg/L (monobromoacetic acid) to 0.34 µg/L (trichloroacetic acid). The performance of the method was checked along different strategic sampling points of three potabilization plants serving the city of Turin (Italy), including intermediate treatments and finished waters. Recovery was checked according to the ±30% limit of acceptability set by EPA regulations. The effect of disproportionate concentrations of chlorite and chlorate in respect to HAAs on HAA signals was studied; this aspect is underestimated in literature. The method is routinely applied by the potabilization plant of the city of Turin to confirm the effectiveness of all control measures in abstraction, treatment, distribution and storage. This study represents the first example in Italy of development and use of a cutting-edge technique for HAAs analysis along the potabilization processes.


Assuntos
Cromatografia , Desinfecção , Água Potável/análise , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise , Acetatos/análise , Bromatos/análise , Cloretos/análise , Cloro/análise , Cidades , Água Potável/normas , Itália , Abastecimento de Água/normas
10.
Emerg Microbes Infect ; 8(1): 1229-1239, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31448697

RESUMO

Lysine acetylation and succinylation are both prevalent protein post-translational modifications (PTMs) in bacteria species, whereas the effect of the cross-talk between both PTMs on bacterial biological function remains largely unknown. Our previously study found lysine succinylated sites on proteins play important role on metabolic pathways in fish pathogenic Aeromonas hydrophila. A total of 3189 lysine-acetylation sites were further identified on 1013 proteins of this pathogen using LC-MS/MS in this study. Functional examination of these PTMs peptides showed associations with basal biological processes, especially metabolic pathways. Additionally, when comparing the obtained lysine acetylome to a previously obtained lysine succinylome, 1198 sites in a total of 547 proteins were found to be in common and associated with various metabolic pathways. As the autoinducer-2 (AI-2) synthase involved in quorum sensing of bacteria, the site-directed mutagenesis of LuxS at the K165 site was performed and revealed that the cross-talk between lysine acetylation and succinylation exerts an inverse influence on bacterial quorum sensing and on LuxS enzymatic activity. In summary, this study provides an in-depth A. hydrophila lysine acetylome profile and for the first time reveals the role of cross-talk between lysine acetylation and succinylation, and its potential impact on bacterial physiological functions.


Assuntos
Aeromonas hydrophila/metabolismo , Proteínas de Bactérias/metabolismo , Liases de Carbono-Enxofre/metabolismo , Lisina/metabolismo , Processamento de Proteína Pós-Traducional , Acetatos/análise , Acetilação , Aeromonas hydrophila/química , Aeromonas hydrophila/fisiologia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Liases de Carbono-Enxofre/química , Liases de Carbono-Enxofre/genética , Cromatografia Líquida , Análise Mutacional de DNA , Lisina/química , Mutagênese Sítio-Dirigida , Percepção de Quorum , Ácido Succínico/análise , Espectrometria de Massas em Tandem
11.
Talanta ; 205: 120107, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31450415

RESUMO

A comprehensive structural characterization of the complex family of isomeric forms related to Oleuropein aglycone (OA) detected in virgin olive oil (VOO) was performed by reverse phase liquid chromatography with electrospray ionization and Fourier-transform mass spectrometry (RPLC-ESI-FTMS), integrated by enzymatic/chemical reactions performed on Oleuropein, the natural precursor of OA. First, some of the OA-related isomers typically observed in VOO extracts were generated upon enzymatic hydrolysis of the glycosidic linkage of Oleuropein. This step mimicked the process occurring during olive drupes crushing in the first stage of oil production. The incubation of the enzymatic reaction mixture at a more acidic pH was subsequently performed, to simulate the conditions of olive paste malaxation during oil production. As a result, further isomeric forms were generated and the complex chromatographic profile typically observed for OA in olive oil extracts, including at least 13 different peaks/bands/groups of peaks, was carefully reproduced. Each of those chromatographic features could be subsequently assigned to specific types of OA-related isomers, belonging to one of four structurally different classes. Specifically, diastereoisomers/geometrical isomers corresponding to two different types of open-structure forms and to as many types of closed-structure, di-hydropyranic forms of OA, characterized by the presence of one or two carbonyl groups, according to the case, were evidenced. In addition, the presence of stable enolic/dienolic tautomers, providing an indirect structural confirmation for some OA isomers, was ascertained through RPLC-ESI-FTMS analyses performed under H/D exchange conditions, i.e. in the presence of deuterated water as one of the mobile phase solvents.


Assuntos
Acetatos/análise , Azeite de Oliva/análise , Piranos/análise , Acetatos/química , Acetatos/isolamento & purificação , Cromatografia de Fase Reversa/métodos , /isolamento & purificação , Deutério , Análise de Fourier , Hidrólise , Iridoides/química , Isomerismo , Extração Líquido-Líquido , Olea/química , Piranos/química , Piranos/isolamento & purificação , Espectrometria de Massas em Tandem/métodos , beta-Glucosidase/química
12.
J Dairy Sci ; 102(10): 8850-8861, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31378500

RESUMO

The objectives of this study were (1) to predict ruminal pH and ruminal ammonia and volatile fatty acid (VFA) concentrations by developing artificial neural networks (ANN) using dietary nutrient compositions, dry matter intake, and body weight as input variables; and (2) to compare accuracy and precision of ANN model predictions with that of a multiple linear regression model (MLR). Data were collected from 229 published papers with 938 treatment means. The data set was randomly split into a training data set containing 70% of the observations and a test data set with the remaining observations. A series of ANN with a range of 1 to 9 artificial neurons in 1 hidden layer were examined, and the best one was selected to compare with the best-fitted MLR model. The performance of model predictions was evaluated by root mean square errors (RMSE) and concordance correlation coefficients (CCC) using cross-evaluations with 100 iterations. When using the ANN to predict ruminal pH and concentrations of ammonia, total VFA, acetate, propionate, and butyrate, the RMSE were 4.2, 41.4, 20.9, 22.3, 32.9, and 29.7% of observed means, respectively. The RMSE for the MLR were 4.2, 37.8, 18.3, 19.9, 29.8, and 26.6% of the observed means. The CCC for ruminal pH, ruminal concentrations of ammonia, total VFA, acetate, propionate, and butyrate were 0.57, 0.49, 0.45, 0.40, 0.52, and 0.40, using the ANN, and 0.37, 0.48, 0.40, 0.29, 0.43, and 0.35, using the MLR. Evaluations of the MLR and the ANN indicated that these 2 model forms exhibited similar prediction errors, with 4.2, 39.6, 19.6, 21.1, 31.3, and 28.1% of observed means for pH, ammonia, total VFA, acetate, propionate, and butyrate. Although the ANN increased the precision of predictions related to ruminal metabolism, it failed to improve the accuracy compared with the linear regression model.


Assuntos
Amônia/análise , Ácidos Graxos Voláteis/análise , Rúmen/química , Acetatos/análise , Animais , Butiratos/análise , Bovinos , Dieta/veterinária , Feminino , Concentração de Íons de Hidrogênio , Modelos Lineares , Masculino , Propionatos/análise
13.
Appl Microbiol Biotechnol ; 103(17): 6989-7001, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31267232

RESUMO

The molecular weight of hyaluronic acid (HA) is a critical property which determines its usage in various biomedical applications. This study investigates the correlation between the availability of a critical cofactor, acetyl-CoA, the concentration of a limiting precursor, UDP-N-acetylglucosamine (UDP-GlcNAc), and the molecular weight of HA (MWHA) produced by recombinant Lactococcus lactis MKG6 cultures. This strain expressed three heterologous HA-pathway genes obtained from the has operon of Streptococcus zooepidemicus in an ldh-mutant host strain, L. lactis NZ9020. A flux balance analysis, performed using the L. lactis genome-scale metabolic network, showed a positive correlation of acetyl-CoA flux with the UDP-GlcNAc flux and the experimental data on HA productivity. To increase the intracellular levels of acetyl-CoA, acetate was supplemented as a pulse feed in anaerobic batch cultures. However, acetate is effectively utilized only in the presence of glucose and exhaustion of glucose resulted in decreasing the final MWHA (1.5 MDa). Co-supplementation of acetate resulted in enhancing the acetyl-CoA and UDP-GlcNAc levels as well as the MWHA to 2.5 MDa. This logic was extended to fed-batch cultures, designed with a pH-based feedback control of glucose feeding and pulse acetate supplementation. When the glucose feed concentration was optimally adjusted to prevent glucose exhaustion or accumulation, the acetate utilization was found to be high, resulting in significantly enhanced levels of acetyl-CoA and UDP-GlcNAc as well as a MWHA of 3.4 MDa, which was sustained at this value throughout the process. This study provides the possibility of commercially producing high MWHA using recombinant L. lactis strains.


Assuntos
Acetatos/metabolismo , Acetilcoenzima A/metabolismo , Ácido Hialurônico/biossíntese , Ácido Hialurônico/química , Lactococcus lactis/metabolismo , Acetatos/análise , Proteínas de Bactérias/genética , Técnicas de Cultura Celular por Lotes , Meios de Cultura/química , Meios de Cultura/metabolismo , Glucose/análise , Glucose/metabolismo , Lactococcus lactis/genética , Análise do Fluxo Metabólico , Redes e Vias Metabólicas/genética , Peso Molecular , Proteínas Recombinantes/genética , Streptococcus equi/genética , Uridina Difosfato N-Acetilglicosamina/metabolismo
14.
Plant Genome ; 12(2)2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31290918

RESUMO

Understanding the genetic architecture of fruit quality traits is crucial to target breeding of apple ( L.) cultivars. We linked genotype and phenotype information by combining genotyping-by-sequencing (GBS) generated single nucleotide polymorphism (SNP) markers with fruit flavor volatile data, sugar and acid content, and historical trait data from a gene bank collection. Using gas chromatography-mass spectrometry (GC-MS) analysis of apple juice samples, we identified 49 fruit volatile organic compounds (VOCs). We found a very variable content of VOCs, especially for the esters, among 149 apple cultivars. We identified convincing associations for the acetate esters especially butyl acetate and hexyl acetate on chromosome 2 in a region of several alcohol acyl-transferases including AAT1. For sucrose content and for fructose and sucrose in percentage of total sugars, we revealed significant SNP associations. Here, we suggest a vacuolar invertase close to significant SNPs for this association as candidate gene. Harvest date was in strong SNP association with a NAC transcription factor gene and sequencing identified two haplotypes associated with harvest date. The study shows that SNP marker characterization of a gene bank collection can be successfully combined with new and historical trait data for association studies. Suggested candidate genes may contribute to an improved understanding of the genetic basis for important traits and simultaneously provide tools for targeted breeding using marker-assisted selection (MAS).


Assuntos
Genoma de Planta , Estudo de Associação Genômica Ampla , Malus/química , Malus/genética , Acetatos/análise , Frutas/química , Frutas/genética , Frutas/crescimento & desenvolvimento , Malus/crescimento & desenvolvimento , Odorantes , Polimorfismo de Nucleotídeo Único , Açúcares/análise , Tempo , Compostos Orgânicos Voláteis
15.
Artigo em Inglês | MEDLINE | ID: mdl-31323559

RESUMO

The present study was conducted to check the comparative qualities of essential oils prepared by hydrodistillation (HD) and supercritical fluid techniques. It constitutes the first attempt to investigate the chemical composition of Daucus carota subsp. maritimus extracts using supercritical fluid technology (SFE) as an environmentally clean innovative method of extraction. The effect of pressure on the nature of extractable substances from wild carrot has been performed at a constant temperature of 50 °C and two different pressures (100 and 300 bar). The experimental results showed that pressure had a significant enhancing effect on the fluid transport properties and therefore on yield values. The extraction yield increases from 1.167 to 2.986% while increasing pressure. The chemical compositions of the essential oils prepared by HD and SFE were analyzed on the basis of gas chromatography-mass spectroscopy (GC-MS). Thus, we noticed that all analyzed samples were enriched in geranyl acetate and ß­bisabolene, and that the quantities of different identified substances were extremely sensitive to the extraction method and to the pressure variation in case of SFE.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Daucus carota/química , Óleos Voláteis/isolamento & purificação , Óleos Vegetais/isolamento & purificação , Acetatos/análise , Acetatos/isolamento & purificação , /isolamento & purificação , /isolamento & purificação , Óleos Voláteis/análise , Óleos Vegetais/análise , Pressão
16.
J Pharm Biomed Anal ; 174: 644-649, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31279894

RESUMO

In this work, fused silica coated by arrayed ZNRs were successfully applied as a sorbent for analysis of polar residual solvents in pantoprazole feedstocks. ZnO nanoparticles were produced and deposited on a fused silica surface applying the dip coating technique and hydrothermal growth to synthesize the arrayed nanorods. The ZNRs array fiber coating was characterized by SEM, EDS, XRD, and TGA. The manufactured SPME fiber was coupled to a glass syringe of 10 µL and applied for the sampling of acetone, n-butanol, dichloromethane, ethyl acetate and methanol for further analysis using GC FID. Optimum operating conditions were determined for the incubation temperature (70 °C), incubation time (15 min), extraction time (120 s), and desorption time (0.6 min). Employing the optimum conditions, the proposed method resulted in a good linearity (> 0.997) and precision (< 7.1%) for the evaluated analytes. Recovery tests were also performed on three levels (below, equal to and above the ICH specification limit for residual solvents in pharmaceutical products). Recoveries ranging from 96% to 107% were obtained. Comparison between the reference method and developed method shows errors smaller than 4%.


Assuntos
Cromatografia Gasosa , Solventes/análise , Óxido de Zinco/análise , 1-Butanol/análise , Acetatos/análise , Acetona/análise , Algoritmos , Calibragem , Cromatografia , Limite de Detecção , Metanol/análise , Cloreto de Metileno/análise , Nanotubos/química , Valores de Referência , Reprodutibilidade dos Testes , Dióxido de Silício , Temperatura Ambiente , Difração de Raios X
17.
Chemosphere ; 233: 67-75, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31170585

RESUMO

Ozone (O3) treatment is an effective strategy in maintaining high efficiency and control of biomass accumulation in gas phase biofiltration. However, little is known about the long-term impact of O3 on the microbial communities. In the present study, two biofilters treating gaseous ethyl acetate were operated continuously for 230 days with inlet loads up to 180 g m-3∙h-1. A biofilter operated under continuous O3 addition (90 ppbv) yielded consistently higher removal efficiency (RE) and elimination capacity (EC) compared to the control system. After 120 days of operation, a lower biomass content accompanied by a pH of 1.5 was observed in the ozonated biofilter, which was 2 units lower compared to the control reactor. Both reactors developed a distinct microbial community composition over the course of 230 days. The bacterial community was dominated in both biofilters by Beijerinckia and Gluconacetobacter, while Rhinocladiella similis, Trichosporon veenhuissi and Exophilia oligosperma were abundant in the fungal community. These findings suggest that ozonation of the biofiltration systems not only reduced clogging, but also contributed to the selection of biomass suitable for degradation of ethyl acetate.


Assuntos
Acetatos/química , Poluentes Atmosféricos/química , Ozônio/química , Eliminação de Resíduos Líquidos/métodos , Acetatos/análise , Poluentes Atmosféricos/análise , Bactérias/metabolismo , Biomassa , Reatores Biológicos/microbiologia , Filtração , Microbiota
18.
Food Chem ; 295: 234-246, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174754

RESUMO

This study investigated the accumulation of esters in three hybrid grape cultivars during berry development under two vintages to elucidate the differentiation on their esters biosynthesis. Results showed 'Moldova' showed lower esters content than 'Campbell Early' and 'Catawba' resulting from its limited AAT gene expression and 20 different encoded amino acids. The volatile esters compositions of 'Campbell Early' and 'Catawba' in both vintages were different. Correlation analysis revealed that concentrations of hexyl acetate, 2-phenethyl acetate, ethyl (E,E)-2,4-hexadienoate and ethyl phenylacetate were related to their corresponding alcohols level, whereas threonine and alanine affected ethyl heptanoate formation. Transcriptome analysis indicated that 1847, 1781 and 1870 DEGs, at E-L 35, 36 and 38, respectively, were characterized between 'Campbell Early' and 'Catawba'. The expression level of genes related to the volatile ester precursors biosynthesis, including PRX-VIT_211s0016g05320, PAO-VIT_217s0000g09100, ACOX-VIT_212s0028g02660, ACOX-VIT_216s0022g01120, echA-VIT_205s0077g00860 and ACOX-VIT_200s0662g00010, exhibited a positive correlation to the concentrations of their corresponding volatile esters.


Assuntos
Frutas/crescimento & desenvolvimento , Proteínas/genética , Vitis/química , Vitis/genética , Compostos Orgânicos Voláteis/análise , Acetatos/análise , Acetatos/química , Quimera , Ésteres/análise , Frutas/química , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/análise , Álcool Feniletílico/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas/metabolismo , Vitis/crescimento & desenvolvimento , Compostos Orgânicos Voláteis/química
19.
Nutrients ; 11(4)2019 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-31010207

RESUMO

Microbial communities are responsible for the unique functional properties of chocolate. During microbial growth, several antimicrobial and antioxidant metabolites are produced and can influence human wellbeing. In the last decades, the use of starter cultures in cocoa fermentation has been pushed to improve nutritional value, quality, and the overall product safety. However, it must be noted that unpredictable changes in cocoa flavor have been reported between the different strains from the same species used as a starter, causing a loss of desirable notes and flavors. Thus, the importance of an accurate selection of the starter cultures based on the biogenic effect to complement and optimize chocolate quality has become a major interest for the chocolate industry. This paper aimed to review the microbial communities identified from spontaneous cocoa fermentations and focused on the yeast starter strains used in cocoa beans and their sensorial and flavor profile. The potential compounds that could have health-promoting benefits like limonene, benzaldehyde, 2-phenylethanol, 2-methylbutanal, phenylacetaldehyde, and 2-phenylethyl acetate were also evaluated as their presence remained constant after roasting. Further research is needed to highlight the future perspectives of microbial volatile compounds as biomarkers to warrant food quality and safety.


Assuntos
Anti-Infecciosos/análise , Antioxidantes/análise , Cacau/química , Chocolate/microbiologia , Fermentação , Alimento Funcional/análise , Compostos Orgânicos Voláteis/análise , Acetaldeído/análogos & derivados , Acetaldeído/análise , Acetaldeído/farmacologia , Acetatos/análise , Acetatos/farmacologia , Aldeídos/análise , Aldeídos/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Benzaldeídos/análise , Benzaldeídos/farmacologia , Culinária , Microbiologia de Alimentos , Humanos , Limoneno/análise , Limoneno/farmacologia , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/análise , Álcool Feniletílico/farmacologia , Paladar , Compostos Orgânicos Voláteis/farmacologia , Leveduras/crescimento & desenvolvimento , Leveduras/metabolismo
20.
Food Microbiol ; 82: 70-74, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31027821

RESUMO

The Volatile organic compounds (VOCs) produced by biocontrol yeast strains which belong to the Wickerhamomyces anomalus, Metschnikowia pulcherrima, Aureobasidium pullulans and Saccharomyces cerevisiae species were identified by solid phase microextraction (SPME) coupled with Gas Chromatography-Mass Spectrometry (GC-MS). Alcohols (ethyl alcohol, 3-methyl-1-butanol and phenylethyl alcohol) and esters (ethyl acetate and isoamyl acetate) were found to be the main VOCs emitted by the yeast strains, which had different production rate over a 16-day period. In addition, the tested yeast strains showed a remarkable ability to consume oxygen and to produce high percentages of carbon dioxide over a 5 days incubation period in a model system. The yeast strains, which were proven to very efficiently suppress in vivo the growth of postharvest fungal by VOCs, also quickly produced high percentages of ethyl acetate and carbon dioxide. . For all these reasons, we believe that the level of yeast biocontrol efficacy through the production of volatiles could be the result of a synergistic effect between VOCs and carbon dioxide in the packaging environment.


Assuntos
Agentes de Controle Biológico/metabolismo , Compostos Orgânicos Voláteis/análise , Leveduras/metabolismo , Acetatos/análise , Álcoois/análise , Dióxido de Carbono/análise , Ésteres/análise , Frutas/microbiologia , Cromatografia Gasosa-Espectrometria de Massas , Metschnikowia/metabolismo , Saccharomyces cerevisiae/metabolismo
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